Guard for punch presses



N A M S m W A. W

GUARD FORl PUNCH PRESSES Filed Nov. l2, 1954 Patented Mar. 10, 1936 UNITED STATES FATENT OFFICE GUARD FOR PUNCH PRESSES William A. Wiesman, Dayton, Dhio Application November 12, 1934, Serial No. 752,689 1s claims. (c1. rzii- 612) This invention relates to guards for punch presses and similar machines. Usually such a guard comprises an arm which is pivotally mounted on the machine and is actuated through suitable connections with the driving shaft, or with the ram itself, to cause the lower portion of the arm to sweep across the machine in front of the work as the ram moves downwardly, thus preventing the hands of the operator from remaining in the path of the ram. In such machines the driving shaft, which operates the ram, is usually arranged crosswise of the machine, that is, parallel with the front thereof, and the guard arm and its operating device are arranged for operation by this crosswise shaft. However, some machines are provided with fore and aft shafts, that is, the shaft is arranged substantially parallel with the sides of the machine. Guard arms which are adapted for operation on a machine having a crosswise shaft cannot be applied to `machines having a fore and aft shaft but a different arrangement and different operating mechanism are required.

One object of the present invention is to provide a guard adapted to be mounted on a punch press or the like having a fore and aft shaft and to be actuated by that shaft.

A further object of the invention is to provide simple and efficient means for pivotally supporting the guard and for actuating the same, which can be quickly and easily applied to such a machine for operation by the fore and aft shaft in properly timed relation to the movements of the ram.

A further object of the invention is to provide an improved pivotal support for the guard and to provide means for mounting said support in different vertical positions with relation to the machine.

A further object of the invention is to provide a pivotal support for the guard which can be adjusted to position the axis at different angles to the horizontal and thereby locate the guard different distances from the work.

Other objects of the invention will appear as the mechanism is described in detail.

In the accompanying drawing Fig. l is a front elevation, partly broken away, of a punch press equipped with my improved guard; Fig. 2 is a side elevation of the guard and its actuating mechanism; Fig. 3 is a detail View of the connection between the guard and the operating shaft; Fig. 4 is a front elevation of a part of the supporting bracket; Fig. 5 is a rear elevation of one of the lateral bearing members; and Fig. 6 is a side elevation of the support for the guard showing the axis in an angular adjusted position with relation to the bracket.

In the drawing I have illustrated one embodiment of my invention and have shown the same ,5 as applied to a punch press of a well known type having a fore and aft shaft. It will be understood, however, that this embodiment has been chosen for the purposes of illustration only and that the invention may take various forms and l0 may be applied to punch presses or other machines of various kinds.

In the particular embodiment here illustrated the press comprises an upright supporting frame IIJ having a work supporting table II which carl5 ries the die I2. A ram I3 is mounted in suitable guides on the machine for vertical reciprocatory movement and carries at its lower end a punch I4 cooperating with the die I2. The operating shaft I5 is mounted above the ram and extends from 20 a point in the rear of the ram to a point adjacent to the plane in which the ram moves, this shaft being mounted in the usual bearings on the frame of the machine, which are not here shown. The forward end of the shaft is provided with an eccentrically arranged trunnion, or wrist pin, I6 which is connected by a pitman I'I with the ram, the wrist pin being preferably arranged directly above the ram. The fly wheel I8 is mounted on the shaft at the rear of the machine.

The guard arm is pivotally mounted on an axis preferably arranged adjacent to the shaft and extending lengthwise thereof. In the present instance, a bracket is mounted on a fixed part of the machine and the arm supporting means is carried by this bracket. In the present form of the apparatus the bracket comprises an upright bar I9 rigidly secured to the main frame of the machine and extending upwardly at one side of the shaft to a point above the same. The upper end portion of this bar is bent forwardly and downwardly and arranged in spaced relation to the body of the bar, as shown at 20. The downturned portion 20 of the bracket is provided with one or more openings. Preferably a vertically arranged series of openings are formed in the bracket, in overlapping relation, so that each opening merges into the adjacent openings, thus providing a longitudinal slot having opposed recesses, each pair of recesses constituting a separateopening, as shown at 2 I. Extending through one of the openings in the bracket is a pivot pin 22 which is here shown as a bolt having both ends screw threaded and provided respectively with nuts 23 and 24. Mounted on this pivot pin, in 55 front of the bracket, are two lateral bearing members or disks 25 and 26, the bearing member 25 being arranged adjacent to the bracket and being provided with studs 21a vertically spaced from the pivot pin and adapted to enter openings in the bracket 20 above and below the pivot pin, so as to hold the bearing member 25 against rotation. The bearing member 26 is supported on the pivot pin in spaced relation to the beaiing member 25 and this bearing member is preferably mounted for axial movement on the pivot pin and a spacing sleeve 21 mounted between the two bearing members. If desired, this spacing sleeve may be formed integral with the disk 26. When the nuts are tightened down the bearing members and the sleeve will be held in rm engagement one with the other. Ordinarily the rictional engagement between the members will hold the outer bearing member 26 against rotation but the inner bearing member 25 may be provided with a dowel pin 28 adapted to enter a suitable opening in the spacing sleeve and when this sleeve is rigidly secured to the bearing member 26 the three members will be held against relative rotation. The tightening down of the nuts also serves to rigidly secure the assembly to the bracket. The guard arm is here shown as comprising an upper tubular portion 29 having rigidly connected therewith a hub 30 which is mounted on the spacing sleeve 21 between the bearing members 25 and 26 and has flat lateral faces opposed to those bearing members. The spacing sleeve is of such a length that the hub will t snugly between the bearing members so as to be held against lateral or tilting movement but will be free to oscillate with relation thereto. Mounted in the tubular portion 29 of the guard arm is a lower portion 3| which may, if desired, be adjustable in the tubular portion and which, as here shown, has its lower end curved and provided with a protecting cover 32, such as a soft rubber tube.

Rigidly secured to the hub 30 of the guard arm is a crank arm 33 which extends laterally from the pivot pin and transversely to the shaft |5, this crank arm being here shown as spaced some distance in front of the forward end of the shaft and at a slightly higher level. This crank arm is connected with the shaft for operation thereby so that as the shaft rotates oscillatory movement will be imparted to the crank arm and to the guard arm. Preferably this connection is effected by a connecting rod 34 pivotally connected at one end of the crank arm and at the other end with the wrist pin |6 of the shaft I5. As here shown, the wrist pin |6 is provided with a bearing member which is preferably in the form of a block 35 provided with a screw threaded stud 36 adapted to be inserted in a suitable opening in the end of the wrist pin. The block is provided in its outer face with a bearing socket 31 which is substantially spherical in shape. A bearing block 38 is mounted on the crank arm 33 and provided in its rear end with a bearing socket 39 which is substantially spherical in shape. Preferably the bearing block 38 is adjustably mounted in the crank arm and is held in adjusted positions thereon by a set screw 40. The connecting rod 34 is provided at its respective ends with oppositely extending spherical heads 4| which are seated in and retained in the spherical bearings 31 and 39, thus establishing universal joint connections between the connecting rod and the wrist pin, and between the connecting rod and the crank arm. Consequently as the wrist pin rotates about the axis of the shaft |5 the connecting rod will impart reciprocatory movement to the crank arm. In the present construction a brace rod 42 is connected at one end with the free end of the crank arm 33 and at its other end with the guard arm to brace the latter against the crank arm.

It is also desirable that the pivotal support for the guard arm should be adjustable so as to support the lower end of the guard arm at different distances from the work as it sweeps across the machine. This is preferably accomplished by so constructing the supporting structure that the axis of the guard arm can be adjusted to different inclined positions with relation to the bracket 2G, thus supporting the guard arm for movement in different inclined planes. As here shown, the bearing member or disk 25 is provided in its lower portion, and in spaced relation to the pivot pin 22, with parts, such as screws 43, which project rearwardly therefrom and are adapted to engage the bracket 20 below the pivot pin. The pivot pin is of a diameter slightly smaller than the holes 2| in the bracket and can therefore be tilted more or less in the bracket. Therefore, by adjusting the screws 43 to cause them to project the desired distance rearwardly from the disk 25 and then tightening down the nuts on the pivot pin the supporting structure will be rigidly secured to the supporting bracket with the pivot pin at an angle to the horizontal, as shown in Fig. 6.

From the foregoing description it will be apparent that the guard arm and its operating mechanism can be quickly and easily applied to a machine of the type illustrated, it being only necessary to provide means for fastening the bracket bar I9 to the frame of the press and to provide the eccentric trunnion I6 with a screw threaded opening to receive the stud 36 of the bearing block 35. The arrangement of the supporting mechanism is such that the arm will be supported in proper relation to the machine and may be adjusted to different positions with relation to the work. The whole construction is simple, easily operated and of a strong durable character.

While I have shown and described one embodiment of my invention I wish it to be understood that I do not desire to be limited to the details thereof as Various modifications may occur to a person skilled in the art.

Having now fully described my invention, what I claim as new and desire to secure by Letters Patent, is:

1. In a machine comprising a reciprocatory member, a shaft extending forwardly from the i rear of said member to a point near the plane in which said member moves, and a pitman operatively connecting said shaft with said member; a guard arm pivotally mounted at one end on an axis substantially parallel with said shaft, a crank arm connected with said guard arm near the pivotal axis of the latter and extending transversely to said shaft, and a connecting member connected at one end with said crank arm and pivotally connected at its other end with said shaft f in front of said pitman and at a point spaced from the axis of said shaft to cause oscillatory movement to be imparted to said crank arm and said guard arm by said shaft.

s 2. In a machine comprising a reciprocatory' member, a shaft extending forwardly from the rear of said member to a point near the plane in which said member moves and having an eccentric portion at its forward end, and means for connecting said eccentric portion with said re- 1 ciprocatory member; a guard arm pivotally mounted at one end on an axis substantially parallel with said shaft, a 4crank arm connected with said guard arm near the pivotal axis thereof and extending transversely to sai-d shaft, a member connected at one end With said crank arm, and means other than the rst mentioned connecting means for pivotally connecting the other end of the last mentioned member with 'the eccentric portion of said shaft to transmit movement from said shaft to said crank arm.

3. In .a machine comprising a reciprocatory member, means vfor imparting reciprocatory movement to said member, a guard arm mounted on said machine for movement about an axis transverse to the plane of movement of said reciprocatory member, and means actuated in accordance with the movement of said reciprocatory member for imparting oscillatory movement to said guard arm; means for adjusting said guard arm with relation to said machine to cause the same to oscillate in a selected plane inclined to the plane o-f said reciprocatory member.

4. In a machine comprising a reciprocatory member, a shaft extending forwardly from the rear of vsaid member to a point near the plane in which said member moves and having an eccentric portion near its forward end,and means for connecting said eccentric portion with said reciprocatory member; a guard arm pivotally mounted at one end on an .axis substantially parallel with said shaft, a crank arm connected with said guard arm near the pivotal axis thereof, a connecting member, and universal joints connecting the respective ends of said connecting member with the forward end of the eccentric portion of said shaft and with said crank arm.

5. In a machine comprising a reciprocatory member, a shaft extending forwardly from the rear of said member to a point near the plane in which said member moves, and means for operatively connecting said shaft with said member; said shaft having at its forward end a bearing spaced from the axis thereof, a guard arm pivotally mounted at one end on an axis substantially parallel with said shaft, a crank arm connected with said guard arm near the pivotal axis thereof, a part mounted on said crank arm for adjustment lengthwise thereof and having a bearing, and a connecting member mounted at its respective ends in said bearings.

6. In a machine comprising a reciprocatory member, a shaft extending forwardly from the rear of said member to a point near the plane in which said member moves and having at its forward end an eccentric portion, and means for operatively connecting the eccentric portion of said shaft with said member; a guard comprising a single arm having a hub at one end thereof, a support on which said hub is mounted for movement about an axis substantially parallel with said shaft, a crank arm connected with said huband extending transversely to said shaft, means for connecting said crank arm with the eccentric portion of said shaft in front of the first mentioned connecting means to cause said shaft to impart oscillatory movement to said crank arm and said guard arm, and a brace connected at one end with said crank arm and connected at its other end with said guard arm at a point spaced from said hub.

7. In a machine comprising a reciprocatory member, a shaft extending forwardly from the rear of said member to a point near the plane in which said member moves, and means for operatively connecting said shaft with said member; said shaft being provided at its forward end with a bearing socket spaced from the axis thereof, a guard arm pivotally mounted at one end on an axis substantially parallel with said shaft, a crank arm vconnected with said guard arm near the pivotal axis thereof, a part carried by said crank arm and having a bearing socket, and a connecting rod having at its ends laterally offset portions seated in the respective bearing sockets.

8. In a machine comprising a reciprocatory member, a shaft extending forwardly from the rear of said member to a point near the plane in which said member moves, and means for operatively connecting said shaft with said member; said shaft being provided at its forward end with a bearing socket spaced from the axis thereof, a guard arm pivotally mounted at one end on an axis substantially parallel with said shaft, a f

crank arm connected with said guard arm near the pivotal axis thereof, a member mounted on said crank arm for adjustment lengthwise thereof and having a bearing socket, and a connecting rod having at its ends laterally offset portions seated in the respective bearing sockets.

9. In a machine comprising a reciprocatory member, a shaft, and means for operatively connecting said shaft with said member; a bracket carried by a stationary part of said machine and having a plurality of holes therein, a pivot pin extending through one of said4 holes, a disk mounted on said pivot pin adjacent to said bracket and having a stud spaced radially from said pivot pin to enter another of said holes and to hold said disk against rotation, a second member mounted on said pivot pin, means carried by said pivot pin to retain said second disk in a fixed position with relation to the first mentioned disk and to secure said pin to said bracket, a

guard arm having a hub mounted on said pivot pin for oscillatory movement with relation to said disks, a crank arm connected with said hub, and means actuated by said shaft for imparting oscillatory'movement to said crank arm and said guard arm.

10.'In a machine comprising a reciprocatory member, a shaft, means for operatively connecting said shaft with said member, a bracket carried by a stationary part of said machine and having a vertically arranged series of holes, a pivot pin adapted to extend through a selected one of said holes and to be adjusted therein about an axis transverse to its length, a disk mounted on said pivot pin and having a stud spaced vertically from said pivot pin to enter another of said holes, a second disk mounted on said pivot pin, a spacing sleeve mounted on said pivot pin between said disks, means for retaining said disks in fixed positions on said pivot pin and for securing said pivot pin in adjusted positions on said bracket, a guard arm having a hub mounted on said spacing sleeve between said disks for oscillatory movement with relation to said disks, a crank arm secured to said hub, and means actuated by said shaft for imparting oscillatory movement to said crank arm and said guard arm.

11. In a machine comprising a reciprocatory member, a shaft, and means for operatively connecting said shaft with said member; a guard arm, means for mounting said guard arm on a xed part of said machine for movement about an axis transverse to the plane of said reciprocatory member and for adjusting the same with relation to said xed part to position said axis at an inclination to the plane of said reciprocatory member, and means actuated in accordance with the movement of said reciprocatory member for imparting oscillatory movement to said guard arm.

12. In a machine comprising a frame, and a member mounted for reciprocatory movement on said frame; a supporting structure carried by said frame, a guard arm mounted on said supporting structure for oscillatory movement in front of said reciprocatory member, means for adjusting said supporting structure with relation to said frame to support said guard arm in different angular positions With relation to the plane of said reciprocatory member, and means actuated in accorda-nce with the movement of said reciprocatory member to impart oscillatory movement to said guard arm.

13. In a machine comprising a frame, and a member mounted for reciprocatory movement on said frame; a pivot pin supported by said frame, a guard arm mounted on said pivot pin for oseillatory movement across the front of said machine, means for adjusting said pivot pin about an axis transverse to its length to locate the free end of said guard arm in different angular positions with relation to said frame, and means actuated in accordance with the movement of said reciprocatory member to impart oscillatory movement to said guard arm.

14. In a machine comprising a frame and a member mounted for reciprocatory movement on said frame; a bracket carried by said frame, a pivot pin vmounted on said bracket for adjustment with relation thereto about an axis transverse to its length, disks mounted on said pivot pin, .one of said disks having a part cooperating with said bracket to hold said disk against rotation, said part being movable With relation to said bracket to permit the adjustment of said disk with said pivot pin, means for securing said pivot pin in its adjusted position on said bracket and for retaining said disks in xed relative positions, a guard arm having a hub mounted on said pivot pin between said disks for oscillatory movement with relation to said disks, and means actuated in accordance with the movement of said reciprocatory member to impart oscillatory movement to said guard arm.

15. In a machine comprising a reciprocatory member, a shaft extending forwardly from the rear of said member to a point near the plane in which said member moves, and means for operatively connecting said shaft With said member; a guard arm, means for supporting said guard arm for oscillatory movement in a vertical plane transverse to said shaft and in front of said reciprocatory member, means for adjusting said supporting means to cause said guard arm to move in a plane inclined to the plane of said reciprocatory member, and means actuated by the rotation of said shaft to impart oscillatory movement to said guard arm.

16. In a machine comprising a reciprocatory member, a shaft extending forwardly from the rear of said member to a point near the plane in which said member moves, and means for operatively connecting said shaft with said members; a guard arm, means for supporting said guard arm for oscillatory movement about an axis substantially parallel with said shaft and in a plane in front of said reciprocatory member, means for adjusting said supporting means to change the position of said axis with relation to said shaft and to thereby change the distance between the free end of said guard arm and said reciprocatory member, and means actuated by said shaft for imparting oscillatory movement to said guard arm.

17. In a machine comprising a reciprocatory member, a shaft extending forwardly from the rear of said member to a point near the plane in which the member moves, and means for opera.- tively connecting said shaft With said member; a bracket carried by a stationary part of said machine and having an opening therein, a pivot pin mounted in said opening and movable to an inclined position with relation to said bracket, a member mounted on said pivot pin in fixed angular relation thereto, an adjustable part carried by said member to engage said bracket at a point spaced from said pivot pin to control the angular position of said pivot pin with relation to said bracket, means for rigidly securing said pivot pin to said bracket in its adjusted position, a guard arm mounted for yoscillatory movement on said pivot pin, and means actuated by the rotation of said shaft to impart oscillatory movement to said guard arm.

18. An automatic guard for a machine including a frame and a member mounted for reciprocatory movement on said frame, comprising a guard arm, means for mounting said guard arm on said frame for oscillatory movement in front of said reciprocatory member and for adjusting said guard arm about an axis substantially parallel with the plane of said reciprocatory member to cause the same to oscillate in a selected plane Which is inclined with relation to the plane of said reciprocatory member, and means actuated in accordance with the movement of said reciprocatory member to impart oscillatory movement to said guard arm.

WILLIAM A. WIESMAN. 

